I'm not sure, since we don't know full power of SR, but I think they can win this by themself.
If Bazz-B win against both Renji and Rukia combined, he could take any of Shinigamis 1 vs 1 (Kenpachi).
Full powered Bambietta could win against Base Aizen, Kubo needed to create Zombie in order to beat her.
Askin was said to be monster, and I believe that he could end being stronger than Greemy, so IMO he should just like Bazz-B be able to beat any of Shinigamis 1 vs 1. (Unohana)
And we are left with As Nodt and Quilge against Tessai, Tessai by my asumptiotion should be around Kyoraku's level and I sure don't see him beating Quilge and As at the same time.
So, SR alone win this with around mid diff.